1. Field of Invention
The present invention relates to an integral heating/cooling system for use with orthopedic or surgical casts, braces or splints. More particularly, the present invention relates to fluid circulating system(s) to be built into a cast, brace or splint to regulate the temperature of the skin beneath such casts to, for example, alleviate pain or swelling.
2. Prior Art & General Background
U.S. Pat. No. 4,308,862 to Kalmar (issued Jan. 5, 1982) teaches the use of tubing in the construction of a plaster cast, but there are many fundamental differences between it and the present invention. For example, the tubes are used for ventilation and the tubing in the Kalmar patent is perforated, so that air in the tubing can escape into the cast. There is no closed system or return flow in the Kalmar device. The tubing is not divided into separable units to provide relief to specific areas. The Kalmar device is directed only to air ventilation of the area covered by the cast and not to controlled temperature regulation.
An article in the February 1956 issue of Braces Today entitled "Water-Cooled Body Casts Described" mentions the work of a Dr. Sullivan at the Mayo Clinic in November of 1955 in which apparently tubing was coiled around a cast prior to completion of the cast. Here again the objective was the overall cooling and general comfort of the patient, but not specific temperature control of selectable areas.
Additional prior patents which may be of interest are listed below:
______________________________________ U.S. Pat. No. Patentee(s) Issue Date ______________________________________ 3,116,731 T. E. Baxter Jan. 7, 1964 3,656,477 Thomas et al. April 18, 1972 3,998,220 Cleer, Jr. et al. Dec. 21, 1976 4,076,019 B. S. Sain Feb. 28, 1978 4,235,228 Gaylord, Jr. et al. Nov. 25, 1980 ______________________________________
The '731, '477 and '220 patents are directed to various types of air ventilating systems for orthopedic casts.
The '228 patent discloses the use of a padding layer and covering fabric of hydrophobic textile material in association with an orthopedic cast material, which acts to wick moisture from the skin of the wearer to the outer surface of the cast material. The evaporation of the moisture is claimed to alleviate skin irritation and odor beneath the cast.
The '019 patent includes the use of a felted layer of polyester or cotton fibers with ground silica-gel to absorb perspiration from the body, claiming to improve the patient's comfort.
Various heating pads of course are also known in which for example a heated liquid is passed through a disposable material which includes fluid passageways for the liquid to pass in and out of, an example being "Duo-Therm" disposable pad made by American Hospital Supply Corp. of Indianopolis, IN.
3. General Discussion of the Invention
Where there are surgical incisions or fractures, there is an increase in swelling and clots, which can be reduced by application of ice or a cold pack. After surgery or fracture, however, a cast is usually applied to the affected area. This prevents the application of ice or a cold pack, because there is no ready way or means of applying ice or a cold pack to the affected area after the cast is applied. However, by means of the present invention, which is affixed to the inside of the cast at the time of lamination, and bodily integrated into the cast structure, the specific affected areas can be cooled (or warmed) at various desirable temperatures, thus reducing swelling and pain.
The present invention provides one or more sealed units of varying sizes and of lightweight but structurally sound construction. Each unit of the total system has an independent inlet port that accepts the hot or cold fluid for circulation throughout a number of for example "U" shaped passages, which form the individual units. The fluid is then expelled through an outlet port and either returned to the reservoir or channeled through the next individual unit in the system. Each unit is positioned inside the cast at a desired location to relieve swelling or pain.
The tubing is affixed to and sandwiched between preferably two opposing sheets of mesh material, the open interstices of the mesh allowing the unit to be bodily incorporated into the cast during the making of the cast.